# CENTURY by Casey REAS

*Art Blocks Curated, project 100 · 1,000 outputs · minted 25 June 2021 · CC BY-NC 4.0*

![CENTURY #676: a translucent dark grey oculus cut into vertical strips and shuffled against a pale grey ground, inside a circular frame](https://media-proxy.artblocks.io/1/0xa7d8d9ef8d8ce8992df33d8b8cf4aebabd5bd270/100000676.png)
*CENTURY #676, held by AB5D: Palette A, two translucent oculi in the same dark grey, eleven shuffled slices. Render: Art Blocks media proxy.*

## The work and its context

CENTURY is Art Blocks project 100 on the contract `0xa7d8d9ef8d8ce8992df33d8b8cf4aebabd5bd270`. The index records 1,000 invocations against a maximum of 1,000, the runtime `p5@1.0.0`, a square aspect ratio, the licence label `CC BY-NC 4.0` without a link, and a price field of 0.1 ETH [^S01]. Reas's mint text opens: "CENTURY is my homage to paintings and drawings from the twentieth century and the countless hours I've spent looking at them" [^S01][^S02].

The same text names the references: the origins of concrete and non-objective art, colour-field painting and minimalism. Its "strongest direct reference" is a group of pictures Ellsworth Kelly made in the 1950s, which he "cut ... into pieces and reassembled them in different orders" [^S01]. It ends with an instruction: "These are landscapes; they look best large and in motion running as live code" [^S01].

Each output is a circle. Inside it, one or two large tilted ellipses (the "Oculi") sit behind a set of thin diagonal bands. The whole picture is then cut into vertical strips of varying width and shuffled, so that the bands and ellipses break and step at every seam. Pressing "1" cuts and shuffles the picture again; "2" puts the strips back in their original order [^S01]. The bands move slowly all the time.

Reas co-founded the Processing programming language with Ben Fry in 2001 and teaches in the Design Media Arts department at UCLA [^S03]. In the Art Blocks interview for CENTURY he said that, apart from his machine-learning work, "I still code everything in Processing" [^S04]. CENTURY is written in p5.js, the JavaScript descendant of Processing, and its code keeps some Processing habits (see Quirks, below).

## Conception and development

CENTURY has a longer history than its mint date suggests. Reas's site dates a solo exhibition titled *CENTURY* to Gallery [DAM] Berlin, 29 September to 27 November 2012, where it lists *Network C*, *Signal to Noise (Software 1)* and related prints [^S05][^S06]. The same page lists a work called *CENTURY* in *Short Cuts* at CentrePasquArt, Biel, from 18 April to 6 June 2015 [^S05]. In the Art Blocks interview Reas put it this way: "I started a different version of CENTURY along another path in 2015, and I pushed it into this direction in 2021" [^S04].

He described the Kelly source as "a series of images created by Ellsworth Kelly in the 1950s where he cut his images into columns and then reassembled them in a different order" [^S04]. He summed up the method as: "The process of composing, slicing, and re-composing is the core of CENTURY" [^S04]. The motion has a second source. Viewers should "run it live to see the subtle motion, a nod to George Rickey," the kinetic sculptor [^S04]. Reas's own project page now frames the work as "a generative system shaped equally by Ellsworth Kelly and George Rickey." It draws on Kelly's "Paris collages of the 1950s", and "from Rickey comes the dimension of motion and, more crucially, the embrace of chance" [^S05].

The 2021 work became the root of a larger body of work under the same name. REAS.com groups under *CENTURY* a set of fxhash "sketchbook" series titled CENTURY-XXX. These include METAKELLY (13 January 2022), METARILEY and METAMORELLET, which it describes as "created quickly, often within a week". The group also covers the homages METASOTO (2022), *Hommage à Molnár* (2023) and METAVASARELY (2023), and *CENTURY 2052* [^S05][^S07]. Reas has also discussed his practice and his Art Blocks work in several filmed conversations, including an Art Blocks session with Ben Fry [^S08]. *CENTURY 2052* was released on Art Blocks on 20 October 2022 as fifty editions that "will 'die' on 20 October 2052" [^S05][^S07].

## How the work was constructed

The program is a single script of 8,975 bytes, SHA-256 `fd6e03daada52c152eb00093d33c0ec56c27b94e120b7b0cef8fb72876409eec`. It was retrieved from the Art Blocks index and read in full. No code is reproduced here [^S01].

To test the reading, the program's random generator and composition logic were re-implemented in Python and run against all 1,000 token hashes. The re-implementation reproduces every published Palette, Oculi, Alpha, Alpha Value, Janky, Line Quantity, Line Color Options and Slice Order value. It also reproduces the oculus sizes, apart from six half-way rounding cases. The exceptions are the five Line Count values and four Slice Count values discussed under Quirks (own computation) [^S01].

The drawing runs in three layers:

1. **The picture.** An off-screen square image receives up to two ellipses and then between 8 and 51 bands. Each band is a thin four-sided shape running from the left edge to the right edge at a slant. Its thickness comes from one of three power curves.
2. **The cut.** The picture is cut into vertical strips between a fiftieth and just over a quarter of the width, with small strips far more common than large ones. The strips are drawn onto a WebGL canvas as textures, in shuffled or original order. If the "Janky" switch is on, each strip except the first and last is also nudged sideways by up to 1 per cent of the width.
3. **The frame.** Four white corner pieces, each bounded by a Bézier quarter-circle, mask the square into a disc. The circle is the last thing drawn, not a boundary the composition knows about, as the earlier AB5D essay also noted (code reading) [^S01][^S09].

In every frame each band's left end moves up or down along a cosine and its right end moves the other way at half the distance, so the bands rock slowly like a balance. The ellipses do not move [^S01].

The published traits follow the program's draws as the table shows. Probabilities are exact, because the generator returns only multiples of 0.001 (see Quirks).

| Trait (program rule) | Published count of 1,000 |
| --- | --- |
| Palette: A (blue, cream, stone, slate) 63.1%, B (rust in place of blue) 32%, C (greys on black) 4%, D (charcoal, pink, cream) 0.9% | A 646, B 307, C 39, D 8 |
| Oculi: ellipses drawn 89.9% | True 903, False 97 |
| Alpha: translucent oculi, 49.9% chance, Palettes A and C only | True 339 |
| Line Quantity: "More" adds 32 bands, 4.9% | More 43 |
| Line Count: 8 plus a cubed draw times 12 (8 to 19; 40 to 51 with More) | 8: 411; 9: 102; 40 or more: 43 |
| Line Color Options: 2 up to the palette's size | 2: 220, 3: 196, 4: 214, 5: 179, 6: 191 |
| Janky: sideways nudges, 29.9% | True 311 |
| Slice Order: shuffled ("Chaos") 97.9%, original order ("Cosmos") 2.1% | Chaos 975, Cosmos 25 |

The background is drawn at random from the palette's own colours. For Palette A, stone was drawn 178 times, cream 177, slate 158 and blue 133. Palette C is the exception: its background is always pure black, a colour that is not in its palette (own computation) [^S01]. Only one of the eight Palette D outputs, #363, has the pink ground [^S01].

## Quirks in the algorithm

A full read of the program, checked against all 1,000 token records by the re-implementation described above, turned up the following.

1. **The seed reads only part of the hash, and less than it seems.** The program takes the first sixteen characters of the hash string. Those include the "0x" prefix, so the seed comes from fourteen hex digits, and parsing them yields a number larger than JavaScript can hold exactly. The generator's first bit-operation then keeps only the low 32 bits. In practice the seed is the last eight of those fourteen digits, with up to three low bits rounded away. The Python reproduction only matched the published traits once it copied this behaviour (own computation) [^S01]. No two tokens share a seed.
2. **A generator with a thousand values.** The xorshift generator returns its state modulo 1,000, divided by 1,000. Every random choice in CENTURY is therefore drawn from 0.000 to 0.999 in steps of 0.001. That is why the palette odds are exactly 63.1, 32, 4 and 0.9 per cent [^S01]. The generator also uses a signed right shift where the textbook xorshift uses an unsigned one (code reading).
3. **The metadata disagrees with the picture for five tokens.** The live script converts the band-count draw to a whole number with p5's `int()`. In p5 1.0.0 this truncates a number, so a tiny value becomes 0 [^S10]. The published Line Count for #19, #62 and #592 is 17, for #291 it is 11, and for #53 it is 9. For all five the program draws a value of 0.001 to 0.003, which truncates to eight bands. The published figures are exactly what one gets by reading the leading digit of that tiny number written in scientific notation. For example, 0.002 cubed times 12 is 9.6e-8, which reads as 9, plus 8 gives 17. The simplest explanation is that the feature script used a string-based conversion (own computation) [^S01]. The live works therefore have 8 bands, not 9 to 17. Because the extra bands consume extra random draws, the published Slice Count for #19, #53, #62 and #592 also differs from the program's (own computation).
4. **Cosmos outputs are cut but show no seams.** All 25 Cosmos outputs publish a Slice Count of 0. The program still cuts them, into between 6 and 24 strips, but lays the strips back in order, so the cuts are invisible [^S01]. This is the whole, uncut Kelly-style picture that the rest of the edition breaks apart.
5. **Traits that do nothing.** Janky nudges apply only to shuffled strips, so the 12 Cosmos outputs labelled Janky True show no nudge. Alpha affects only the oculi, so the 31 outputs with Alpha True and Oculi False show no translucency; #554 is one [^S01]. In 262 outputs fewer band colours appear than the Line Color Options trait allows, because each band picks its colour at random. In 690 outputs at least one band shares the background colour and reads as a cut rather than a line (own computation).
6. **A second oculus in the background colour.** The first ellipse's colour excludes the background, but the second ellipse's does not. In 236 outputs the second oculus is drawn in the background colour. It is visible only where it covers the first oculus or the bands, and there it appears as a bite taken out of them (own computation) [^S01].
7. **Processing habits in JavaScript.** Several arrays are started as a one-item list holding a size, such as 50 for the slices and 2 for the oculi. That mirrors Processing's Java syntax for an empty array of that length. Every band's speed is drawn from a range whose two ends are both 0.01, which uses up a random number and returns a constant. A call to `pixelDensity()` with no argument only reads the setting and changes nothing (code reading) [^S01].
8. **One shared rhythm.** Because every band rotates at the same 0.01 radians per frame, the whole picture repeats about every 628 frames, roughly ten seconds at 60 frames a second. The speed of the motion depends on the frame rate, not the clock (code reading) [^S01].
9. **Resolution and re-cutting.** The canvas is the smaller of the window's width and height, and every dimension scales with it, so the picture is resolution-independent apart from the whole-pixel nudges. Pressing "1" draws new cuts from the same seeded generator. The sequence of re-cuts is therefore the same each time the page is reloaded. It also turns a Cosmos output into a shuffled one (code reading) [^S01].
10. **Unreachable extreme.** The formula allows 20 bands in the plain setting, but only for a draw of exactly zero. No token reaches it. The published maximum is 19 [^S01].

## The most coveted variants

No published collector guide to CENTURY was found. The evidence for what collectors and institutions value comes from the auction record, the Toledo loans and the distribution of holdings in the index.

**Cosmos (25 of 1,000).** The ordered outputs show the composition before it is cut: continuous bands and whole ellipses inside the circle. Both CENTURY lots in Sotheby's "Grails: Property from an Iconic Digital Art Collection Part II" on 15 June 2023 were Cosmos outputs: lot 11, CENTURY #25, and lot 12, CENTURY #843 [^S11][^S01]. At retrieval both sat in the same wallet. That wallet holds 18 CENTURYs, including four Cosmos and two of the eight Palette D outputs; no source inspected names it [^S01]. #0, the first mint, is also a Cosmos, and so is #554, lent to Toledo [^S01][^S12].

![CENTURY #25: uncut blue diagonals and pale translucent ellipses on cream](https://media-proxy.artblocks.io/1/0xa7d8d9ef8d8ce8992df33d8b8cf4aebabd5bd270/100000025.png)
*CENTURY #25, a Cosmos, offered as lot 11 at Sotheby's in June 2023. Render: Art Blocks media proxy.*

**Cosmos with More lines (3).** Only #0, #448 and #904 combine the ordered strips with the "More" band setting. #904 also has no oculi, so it is an unbroken field of bands on a slate ground [^S01].

![CENTURY #904: dozens of unbroken pale and salmon diagonals on dark slate](https://media-proxy.artblocks.io/1/0xa7d8d9ef8d8ce8992df33d8b8cf4aebabd5bd270/100000904.png)
*CENTURY #904, the only Cosmos with More lines and no oculi. Render: Art Blocks media proxy.*

**Palette D (8).** The rarest palette pairs charcoal with a dusty pink and cream: #147, #173, #261, #363, #481, #540, #561 and #593 [^S01]. #363 is the only one on a pink ground.

![CENTURY #363: pink and cream shapes cut into stepped vertical strips](https://media-proxy.artblocks.io/1/0xa7d8d9ef8d8ce8992df33d8b8cf4aebabd5bd270/100000363.png)
*CENTURY #363, the only Palette D output on a pink ground. Render: Art Blocks media proxy.*

**Palette C (39).** The grey palette on black is the only one whose background comes from outside the palette. #913 combines it with More lines and translucent oculi. It was one of the CENTURYs lent to Toledo [^S01][^S13].

![CENTURY #913: grey and white bands over translucent grey forms, sliced into columns on black](https://media-proxy.artblocks.io/1/0xa7d8d9ef8d8ce8992df33d8b8cf4aebabd5bd270/100000913.png)
*CENTURY #913, Palette C with More lines, shown in "Infinite Images" at Toledo. Render: Art Blocks media proxy.*

**CENTURY #999** was featured in "Coded Elegance", the 1stDibs NFT exhibition curated by Sarah Meyohas. The Mint article on it quotes Reas's mint text [^S14][^S15].

## Exhibitions

- **The Digital**, Miami Art Week, 3 to 5 December 2021, curated by Sofia Garcia. REAS.com lists *CENTURY* among the works shown [^S05].
- **Coded Elegance**, 1stDibs, 2022, with #999 [^S14][^S15].
- **Infinite Images: The Art of Algorithms**, Toledo Museum of Art, 12 July to 30 November 2025, curated by Julia Kaganskiy [^S05]. The exhibition site lists 22 CENTURY tokens: #2, #54, #64, #78, #109, #296, #329, #395, #460, #470, #486, #506, #554, #587, #693, #752, #760, #789, #852, #913, #915 and #945. Each is credited to a "Private collection" and dated "2021, 2025" [^S12][^S13]. The site describes each work as "an abstract moving image that is always in flux" and gives the "1" and "2" key instructions [^S12][^S13]. At retrieval, all 22 sat in two wallets, holding 13 and 9 of them [^S01].

No prints, plotter works, physical editions or book dedicated to CENTURY (2021) were found. Reas's books page lists no CENTURY title, and the "related prints" on his site belong to the 2012 exhibition, not the Art Blocks work [^S16][^S05].

## The mint

Invocation 0 was minted on 23 June 2021 at 20:11:32 UTC, two days before the public sale. The index records activation on 24 June at 16:09:06 UTC [^S01]. The public mint opened on 25 June at 18:59:48 UTC, and the 1,000th token was minted at 19:06:30 UTC, under seven minutes later. The busiest minute, 19:00 UTC, saw 234 mints (own computation) [^S01]. The indexed price is 0.1 ETH [^S01].

At retrieval the 1,000 tokens were held by 509 addresses; 370 held one each and the largest wallet held 39 [^S01]. The index's lowest listing was 0.495 ETH [^S01]. VERSE gave a total sales volume of $991,532 and a highest sale of $53,068, without naming the token or date [^S17].

## Copyright and licensing

The index records `CC BY-NC 4.0` without a link [^S01]. On that label, images of the work may be shared and adapted non-commercially with attribution, and commercial use needs permission. The program carries no separate code licence, and p5.js 1.0.0 is loaded by the platform when the work is viewed [^S01].

## Significance and limitations

CENTURY turns a mid-century studio gesture into a program: Kelly's cutting and reordering, set in Rickey-like motion and applied to a thousand pictures. The viewer can repeat the cut indefinitely. It is also the anchor of a decade-long body of work under the same name, from the 2012 Berlin exhibition to CENTURY 2052 and the METACENTURY homages [^S04][^S05]. The code is short and legible, and it keeps traces of the Processing idiom its author co-created. Its surprises are small but real. The seed ignores most of the hash, the generator has only a thousand values, and five tokens publish a band count their live code does not draw.

The collecting record is thin. Beyond the two Sotheby's lots, the 1stDibs feature and the 22 Toledo loans, no sale price for a named CENTURY was confirmed.

Unresolved research questions:

1. What did CENTURY #25 and #843 fetch at Sotheby's in June 2023, and what were their estimates? The results pages were not readable.
2. Which token holds VERSE's $53,068 highest sale, and when did it sell?
3. Did the 2012 Gallery [DAM] and 2015 CentrePasquArt versions of CENTURY share code or imagery with the 2021 work? Reas's own posts on X may say, but X could not be read.
4. Were the five Line Count errors known to the artist or Art Blocks, and does the Art Blocks site still show the published values?
5. The quotations from Reas's interview, REAS.com, the Toledo pages and the 1stDibs article came from automated WebFetch extraction and should be checked against the live pages.

## Bibliography

### Primary

[^S01]: Art Blocks public GraphQL index, `projects_metadata` for project 100 (including the full program and mint text) and `tokens_metadata` for all 1,000 tokens. Retrieved 20 September 2026 via https://artblocks-mainnet.hasura.app/v1/graphql. Collection page: https://www.artblocks.io/collection/century-by-casey-reas
[^S02]: Casey REAS, "CENTURY", REAS.com project page. https://reas.com/century_s/
[^S05]: Casey REAS, "CENTURY", REAS.com overview with exhibition history. Read September 2026. https://reas.com/century
[^S04]: Jeff Davis, "In Conversation with Casey REAS on CENTURY", Art Blocks (date not shown on page). https://www.artblocks.io/articles/in-conversation-with-casey-reas-on-century
[^S07]: Casey REAS, "NFTs", REAS.com. https://reas.com/nfts
[^S16]: Casey REAS, "Books", REAS.com. https://reas.com/books
[^S10]: p5.js 1.0.0, npm package `p5@1.0.0`, `lib/p5.js`, definition of `int()`. https://www.npmjs.com/package/p5/v/1.0.0
[^S03]: Wikipedia, "Casey Reas". https://en.wikipedia.org/wiki/Casey_Reas

### Exhibitions and institutions

[^S12]: Toledo Museum of Art, "Infinite Images: The Art of Algorithms", Century #554. https://infiniteimages.toledomuseum.org/artwork/century-554
[^S13]: Toledo Museum of Art, "Infinite Images", Century #789, with links to the other Century works shown. https://infiniteimages.toledomuseum.org/artwork/century-789
[^S06]: Artsy, "Casey Reas | Century", DAM, Berlin, 29 September – 27 November 2012. https://www.artsy.net/show/dam-gallery-casey-reas-century

### Video and audio

[^S08]: Video, confirmed via YouTube oEmbed on 20 September 2026 (identified, not watched for this draft):
    - "Episode 14: Art Blocks After Dinner Mints w/ Ben Fry & Casey REAS", Art Blocks Official. https://www.youtube.com/watch?v=HLYKz1DaJQI
    - "Pioneering computational art ft. Casey Reas", Kaloh's Podcast. https://www.youtube.com/watch?v=JOuM0We1Kn8
    - "Casey Reas: Interview Excerpts from CLOUDS (2014)", The Frank-Ratchye STUDIO for Creative Inquiry. https://www.youtube.com/watch?v=VwxOMvzxgpU

### Criticism, collecting and market

[^S11]: Sotheby's, "Grails: Property from an Iconic Digital Art Collection Part II", 15 June 2023, lots 11 (CENTURY #25) and 12 (CENTURY #843). https://www.sothebys.com/en/buy/auction/2023/grails-part-ii
[^S14]: 1stDibs, "CENTURY #999", featured in Coded Elegance. https://www.1stdibs.com/nft/art/century-999/id-n_dpNqt2XnAJ
[^S15]: Alexandra Zagalsky, "Sarah Meyohas, of Bitchcoin Fame, Curates a Brilliant Show of Generative Art", 1stDibs: The Mint, 9 September 2022. https://www.1stdibs.com/the-mint/sarah-meyohas-bitchcoin-exhibition/
[^S17]: VERSE, "CENTURY by Casey Reas", series page. Read September 2026. https://verse.works/series/century-by-casey-reas
[^S09]: AB5D, "CENTURY by Casey REAS", earlier series essay. https://ab5d.xyz/series/century-by-casey-reas/

### Further reading

- Le Random, "Casey Reas on the History of Generative Art, Part 1". https://www.lerandom.art/editorial/reas-history-1
- Right Click Save, "Infinite Images: The Art of Algorithms". https://www.rightclicksave.com/article/infinite-images-the-art-of-algorithms-toledo-museum-of-art-generative-art
- OpenSea, "CENTURY by Casey REAS" collection page. https://opensea.io/collection/century-by-casey-reas