J. M. E. McTaggart

J. M. E. McTaggart was a British idealist philosopher and Hegel scholar who spent his career at Trinity College, Cambridge. In "The Unreality of Time" (1908) he distinguished the A-series, ordering events as past, present and future, from the B-series, ordering them as earlier and later, and argued that time requires the A-series but that the A-series is contradictory, so time is unreal. The distinction remains the standard framework for debates in the philosophy of time.

Key ideas

• The A-series orders events as past, present and future; the B-series orders them as earlier than and later than.
• Real change requires the A-series, since B-series relations never change.
• Every event would have to be past, present and future, incompatible properties, and attempts to avoid this lead to a vicious regress.
• Reality is ultimately a timeless community of selves related by love.

Major works

• Studies in the Hegelian Dialectic (1896)
• Some Dogmas of Religion (1906)
• "The Unreality of Time" (1908, Mind)
• The Nature of Existence (2 vols., 1921 and 1927)

In the conversation

• Question My son says a philosopher proved time is unreal. What are the A-series and B-series? Akosua Mensah · 4 replies
• Reading group Reading group: McTaggart’s ‘The Unreality of Time’ and Prior’s ‘Thank Goodness That’s Over’ Tomasz Szewczak · 5 replies