Saying that humans are not able to pursue something disinterestedly is also an unfounded presupposition. I assume that with “disinterested” is meant “without particular subjective interest”. So the presupposition is that humans always pursue something for their own particular reasons. This presupposes an idea of man that is not so obvious as you might think. The whole philosophical and religious tradition up until the 19th century thought man was special, in that man alone was able to have contact and insight in the infinite/the objective order (compared to other animals). This insight in the objective/infinite is meant when it is said that man can pursue truth in a disinterested way. I just want to point to the fact that the position that man can’t pursue philosophy disinterestedly is not so obvious as it may sound - rather, it is steeped in contemporary ideas about humanity and really not very critical at all. As so often, the more obvious an idea sounds, the less its implicit presuppositions are explicitly present in one’s mind

Saying that humans are not able to pursue something disinterestedly is also an unfounded presupposition. I assume that with “disinterested” you mean “without particular interest”. So your presupposition is that humans always pursue something for their own particular reasons. This presupposes an idea of man that is not so obvious as you might think. The whole philosophical and religious tradition up until the 19th century thought man was special, in that man alone was able to have contact and insight in the infinite/the objective order (compared to other animals). This insight in the objective/infinite is meant when it is said man can pursue truth in a disinterested way. I just want to point to the fact that your position is not so obvious as you make it sound - rather, it is steeped in contemporary ideas about humanity and really not very critical at all.