Max Hodak Writings

What is your ideal body?

August 2020

If you could look like anything – no really, anything – what would you choose? I’m not talking about aesthetics, but what sensory faculties and motor capabilities you’d have. Like: would you have legs? Would you be lighter than air? Use powered flight to get around?

I’ve spent a lot of time thinking about this and have come to the conclusion that the sensory faculty I’d most want to alter is my vision: it would be very interesting to go from passive stereo color vision to a 360-degree bubble of active hyperspectral vision.

Our eyes extract color information from the world through (for most people) three types of cone cells in the retina that are sensitive to different wavelengths of light. This sends a three-dimensional representation of color information for a point in the retinal image down the optic nerve; this is why we can represent our color space in terms of “red-green-blue” or “RGB”. (Also, realize that there is no such thing as a white photon: the color white is a lack of spatiotemporal resolving power in the brain, causing information to be lost.)

There is a ton more information hidden in the distribution of photon energies hitting the retina! Instead of simply detecting power in three broad bands of spectrum and summing them to a color, we could use a hyperspectral imaging sensor to sample many wavelength-powers of the incident light to generate an approximation of the whole continuous radiation spectrum. Our current vision is approximately 4D: we can localize a colored point in 3D space. (Not really, but you can think of it this way.) Hyperspectral vision would be 5D: the ability to perceive depth in the color itself at a point in 3D space, and ideally with an unlimited field of view.

This is way more information. Hyperspectral imaging is used today for things like medicine, geology, astronomy, and a lot more. Imagine being able to just look outside your window and having dozens of new meaningful dimensions of depth to what you’re seeing.

Going even further: our vision now is passive in that it receives energy from the environment but does not not actively probe. If it’s dark, we need a flashlight to make it easier to see. But imagine adding a tunable laser to our vision system: because of how light interacts with materials in the environment, we can extract an vast amount of information from the evoked spectra.

For example, if we apply photons of a certain energy to something within our field of vision, does it fluoresce? (That is, does it emit photons of a different energy?) Many questions in physics, chemistry and biology can be answered by asking whether something fluoresces when excited by a some particular wavelength of light. I think that this sense would be somewhat similar to olfaction, but at a distance, and probably more similar to how a dog smells than how we do. (With depth, able to separate the components being smelled.)

An extreme version of this, which I’m not sure would actually work in daylight given how small the effect is, would be generating Raman spectra for things in your vision, which would completely change our relationship to the world. Imagine if you could generate a nutrition facts label for any food by simply looking at it.

Relatedly, for several years now I have believed that keeping a brain alive will turn out to be a significantly easier problem than comprehensively curing cancer for the rest of the body. As you get older, the body becomes increasingly frail until it eventually becomes a net liability to your consciousness. There has been some work on this, most notably some fairly insane (and possibly fraudulent) experiments by the Soviets in the 1940s, some limited work in monkeys in the 1960s, but also more recently in swine at Yale in 2019. I’ve written about this idea in my fiction, too.

How appealing this kind of procedure would be depends heavily on what the experience of being a brain in a vat would be like, which means neural interfaces need to mature substantially before this kind of work becomes relevant to medicine. But I think that, long term, what people really want is not their body back, but bodies that they never could have imagined before, whether for a simulated reality or the real one.