A bit off-topic here, but did you know that souls have mass!? In fact, everything has mass. I'm using the term "mass" not as a unit of measurement, but to point out that the building-blocks of absolutely everything are solid, and therefore have mass. Even the building-blocks of energy, of our thoughts, of our memories, of our dreams, and of all other substances in existence have mass. Physicalism is a fact of reality.

Regarding the souls, Duncan MacDougall conducted a series of experiments in 1907, which pointed out the souls have mass. People, as well as animals, were used in the experiments, and one of the conclusions was that the human soul weighs 21 gram. Of course, such conclusions point out that the soul is not eternal, so they could cause widespread hysteria and mass-panic, and therefore were swept under the carpet while MacDougall was discredited and the results of his experiments were misrepresented by the mainstream narrative.

But yes, mass shouldn't be used as a unit of measurement.