I believe him, but there are still questions about Soylent’s healthfulness. Though Mr. Rhinehart spent months living on nothing but Soylent and claims it improved his health, the firm has not performed any large-scale studies to show that drinking Soylent over an extended period of time is good for you, or even that it’s not bad for you. Mr. Rhinehart said the firm was conducting a large study, but he declined to divulge any details or a timeline for when it might post results.

Soylent’s biggest failing, though, is its stultifying utilitarianism. Even Mr. Rhinehart describes Soylent mainly in terms of its functional promise. “The most important aspect of this product is simplicity,” he told me. “We’re trying to abstract away the complexity. Here’s this drink that has everything you need, so if it’s your go-to meal, you don’t have to worry about anything else.”

But there is something troubling about the notion of a “go-to meal.” During the last week and a half, I consumed Soylent for most, but not all, of my meals. There were a couple of days when more than 90 percent of my calories came from the powder. At first, as Mr. Rhinehart promised, I did find Soylent to be extremely convenient. It alleviated some of the stress I often feel when I’m pressed for time on a busy workday and need to find something healthy to eat.

That feeling faded. The longer I used it, the more Soylent began to feel like a chore. I began to yearn for the mechanics of solid meals — chewing, swallowing, using my hands and silverware and experiencing a variety of textures and temperatures. I missed crunchy foods, salty foods, noisy foods and hot foods. (Soylent, like revenge, is best served cold.)

Most of all, I missed variety. Soylent’s instructions suggested adding peanut butter, fruit, vanilla extract or other flavorings to the drink. I did, but still, Soylent tasted pretty much the same from day to day — like gritty, thinned-down pancake batter, inoffensive and dull.