 A fourth meaning of rationality, called substantive rationality by Max Weber (1905), applies to the evaluation of your aims of inquiry. Substantive rationality invokes a Kantian distinction between the worthiness of a goal, on the one hand, and how well you perform instrumentally in achieving that goal, on the other. Aiming to count the blades of grass in your lawn is arguably not a rational end to pursue, even if you were to use the instruments of rationality flawlessly to arrive at the correct count.