One way to tell the difference between an optimist and pessimist is well known.
Show them a glass with liquid up to the middle, and ask if it is half full or half empty.
Perhaps for football supporters it should be showing them a team top of the league, and then asking if things are going well or not.
In the aftermath of defeat to Sevco at New Year, many Celtic supporters have fallen into the ‘half empty’ camp.
Some people seem to think the result signals a sea change in fortunes, with Sevco now the country’s top team.
But instead the perspective that time offers is needed.
The loss at Celtic Park was undeniably a setback.
Victory would have, in many ways, ended the league title as a contest. Even a draw would have left Celtic well in front of their nearest rivals.
Sevco’s win has changed that, and they can, in theory at least, take top spot after playing their game in hand.
But that is not the full story of the season so far.
We are halfway through the season, and there are three measurements of progress so far; the league, League Cup and Europe.
The reality is that on all three criteria, Celtic’s exploits can be filed in the ‘very positive’ column.
In Europe, initial disappointment aside, the club have had the best year in recent memory.
Not only topping the Europa League group, but doing so with a game to spare, as well as two amazing wins versus Lazio.
The League Cup is equally a success story.
Another victory – the tenth trophy in a row – even when conceding a penalty and playing with ten men for much of the final.
And with the league season in its Winter break, Celtic are still top of the pile, edging towards a potential ninth league title in a row.
But of course the loss which ended 2019 suggests at least a cloud on the horizon.
It is certainly true that the past two games versus Sevco have seen Celtic often outplayed, but that isn’t close to being the full story.
Celtic and Sevco have met three times in the current campaign, and Celtic have won two of them.
Even in the defeat – and for all Celtic were second best in many ways – other facts paint a different picture, not least possession and shots on target where Celtic were far superior.
In other words, for all it may seem to feel otherwise, Celtic are well ahead in Glasgow derbies this season.
Celtic are five months away from a record breaking season, and less than 18 months from potentially making Scottish football history.
Such an opportunity may never again present itself.
With the right investment, we can settle once and for all the glass half empty or glass half full debate by May this year.
The cups should simply be full, not least the three hopefully to be found in the Paradise trophy room.
Matthew Marr is a Celtic fan from Glasgow. He is a frequent contributor to the site.