The fact of death?

Many human activities gain their meaning from the fact that they are unrepeatable. We make choices, decisions that shape the people we become. Our joy in the immediate experience of the pattern of light and shade in a forest partly comes from the fact that it is a transient effect that we may never see again. Our mortality makes us value the present because we may not have a future. The pattern of our choices and the things that happen to us give us our personal history. Yet if we are going to live for ever after death, this source of meaning won’t be there for us. There will always be time to do everything. Bernard Williams (1929–2003) argued that such immortality would be tedious and ultimately meaningless. It is the fact of death and its finality that gives our lives much of the meaning that they have.

[Philosophy : The basics]

What does "the fact of death" mean? I don't know whether "the fact" is redundant or not. Does "the fact of death just "death"?

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