What is an "alternative fact"?

Sunday morning following the 2008 Trump inauguration, NBC´s Chuck Todd questioned statements made by Whitehouse spokesman Sean Spicer concerning proof of the actual size of the turnout for the event.

When asked about this, Kellyann Conway told Chuck that Sean was only offering "alternative facts", to which Todd replied, "Alternative facts are just falsehoods".

Is there such a thing as an "alternative fact"? Is this another way to say "facts which present an alternative view"?

[EDIT]

A simple ngram search shows this is not a new usage.

And I found numerous usages of the phrase. Here is one, in an appropriately titled book.

from Dimensions of Change: Conceptualising Reality in Organisational Research By Lars Bo Henriksen

Solution 1:

"Alternative facts" is a US legal practice phrase that is over 100 years old.

For example:

From Family Law in Practice:

Provided the alternative facts or the alternative interpretation you put is reasonable, an expert who resists such a suggestion looks less credible.

From Guide to Computer Forensics and Investigations (2014):

You might want to address alternative facts, however, if they allow your opinion to remain the same. The expression “alternative facts” might seem contradictory, but it simply means competing facts. In a civil case, if there weren't alternative possible facts, the case wouldn't be at trial; it would have been decided at summary judgment.

From The Art of Lawyering (2010):

The proof will be in the experts' ability and willingness to handle alternative facts in their own theories or to apply alternative methods than the ones upon which they rely.

And even over 100 years ago The Lawyers Reports Annotated, Volume 51 (1913)

There is no effort in this pleading to allege alternative facts.

So "alterative facts" is a competing version of what the events actually were, based upon evidence availible.

Solution 2:

So, the question is

and the answer is

Solution 3:

In physical sciences, an alternate fact is a true statement that, while appearing to contradict another fact, actually illuminates the subject to greater depth. For example, is light a particle or a wave?

In political debate, an alternative fact is a statement that, although demonstrably false, is treated as a tribal talisman and acted on as though it were true

*Source Facebook comment thread.

Solution 4:

Bertrand Russell in his introduction to the Tractatus Logico-Philosophicus says that facts are what make propositions true. Suppose we have a fact A and that the proposition "A is true" is true and we have an alternative fact B and "B is true" is also true. In itself this is not a problem and so there can be alternative facts. For example if A is "I own a cat" and B is "I own a dog". However if A and B contradict each other then any reader of Aristotle or George Boole or even Ayd Rand would tell you that both A and B cannot be true. So, yes there are alternative facts but there are none that contradict other facts.
If you own both a cat and a dog then yes, both A and B can be true- simultaneously.