(2) The retrospective attribute of blame is incompatible with being a genuine source of reason for moral obligation.

Another attribute of blame distinctive from other attitudes such as belief or desire which makes blame undesirable to be a signpost for the existence of normative reason for moral obligation is that blame is retrospective. One has to wait until after events have occurred to determine warranted blame. Some may argue that blame can be prospective because you may blame a potential act. However, blaming a potential act, with its uncertainty of whether the act will actually occur and whether there may be justified excuses, is not the kind of warranted blame in Darwall’s argument where the aim is a conceptual guarantee.

Part of blame’s retrospective feature is that it is consequence dependent. A moral agent is often not blamed if the consequence is benign. A drunk driver running a red light unobserved and without consequence may escape blame with the excuse that no one is hurt while the same act having the consequence of a tragic accident will likely result in a warranted blame. This retrospective, consequence dependent feature of blame may not in itself dissolve Darwall’s argument that a warranted blame is a signpost for complying with a moral obligation because examination can be limited to the scenario where there is warranted blame. However, allowing blame to only signpost normative reasons for moral obligations with consequences may render a moral act consequence dependent, which risks challenging the most basic premise that Darwall relies on – that moral normativity exists.

On the other hand, a moral obligation is prospective, its command providing guidance for how a moral agent ought to act. While attitudes such as belief or desire would have no issues being a source of reason for why a moral agent chooses to be moral, blame, as a retrospective reactive attitude, is incapable of being a source of genuine reason for why a moral agent complies with a moral obligation. If blame were to be the source of reason, owing to blame’s nature of being adduced after the fact, the moral agent would have to take a look into the future before arriving at a reason to comply with a moral obligation. A source of reason that rests on the future is incapable of providing a conceptual guarantee.