COGITO, ergo sum. Three words which came to define Western philosophy in the face of modern times during the Enlightenment.

For Celtic, holding onto that edict – however outdated and superseded it has become – can prove fruitful in their endeavours at the elite level of European football. For if Brendan Rodgers is to achieve his objective of progressing his side in European competition, the Celtic manager perhaps has to start from the position of thinking primarily as a European club, and let go of his reputation as a domestic tsar – in cup competitions at least.

The Herald: Brendan Rodgers poses with the league, Scottish Cup and League Cup trophiesBrendan Rodgers poses with the league, Scottish Cup and League Cup trophies (Image: SNS)

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When old Rene Descartes first chalked this tripartite motto onto a slate in the original Latin, the French thought-boffin had the inspired idea to translate it into his own native tongue so that his mates down at the student union might actually have a clue what he was banging on about. “Je pense, donc je suis”. Got it now? No, me neither. But suffice to say it caught on. “I think, therefore I am” (as it dilutes down to in English) was considered proof of the existence of the self. So the idea goes, "If I can think, I must be" - even if the idea was then scrutinised and debunked for centuries thereafter. And that’s how these things tend to go: one minute you’re the high priest of cartesian philosophy like the redoubtable Rene, the next your approach is being picked apart and deconstructed by the next generation like an old cardboard box in a nursery play area.

When Brendan Rodgers reinvented the ancient philosophy known as The Celtic Way by bulldozing to an invincible treble, the Northern Irishman could do no wrong in the eyes of his Parkhead devotees. By the time he had pulled up at the King Power Stadium to become Leicester City manager in 2019, however, his reputation had been crumpled up and flat-packed by many of those who heralded his first coming. “But what did he do in Europe?”, an oft-heard counterpoint to the messiah thesis. 

Celtic, the first British club to lift the European Cup back in 1967, have a rich and well-versed history in continental competition. Jock Stein’s side missed out on repeating the feat after extra-time against this year’s Champions League Group E rivals Feyenoord three years later. Flirtations with the latter stages of Europe’s premier competition would continue into the next decade, with the infamously ill-tempered semi-final defeat to fellow Group E outfit Atletico Madrid in 1974 the closest the Glasgow giants ever came to restoring that former glory.

The Herald: Celtic's Lisbon Lions lift the European Cup in 1967Celtic's Lisbon Lions lift the European Cup in 1967 (Image: SNS)

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Martin O’Neill reached extra-time in the 2003 UEFA Cup final where his side eventually lost to the following season’s Champions League winners Porto under Jose Mourinho. Was the pinnacle of Europe’s second tier their true level in the modern era? If Descartes attended a symposium on “Are Celtic still a Champions League team?” he would probably recite his greatest hit: “I think, therefore I am”. Celtic, for the past two seasons, are self-evidently a Champions League club. And despite the ever-stretching gulf to the continent’s wealthiest cubs since O’Neill’s departure – as the baton of financial and sporting might has been passed like 17th-century strands of philosophy around the esteemed Italian, English, Spanish, German and French leagues – the Parkhead side have enjoyed positive results in European competition against Manchester United, Udinese, Rennes, Barcelona, Villareal, Inter Milan, Manchester City, Borussia Moenchengladbach, RB Leipzig, Lazio, Rennes, Real Betis, and now Atletico Madrid of those major leagues.

The Herald: Ewan Henderson scores to make it 2-1 to Celtic against Real Betis in 2021Ewan Henderson scores to make it 2-1 to Celtic against Real Betis in 2021 (Image: SNS)

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In truth, it is a bit of a daft edict, really, “Cogito, ergo sum”. If nothing else, three-word slogans remind us of the power of threes. Three, as we all know, is a magic number. Take the treble, for example. Celtic’s uncanny proficiency in achieving that feat – they have won five domestic trebles in their previous seven season, one of the spares including a league and cup double – will forever be etched into the club’s annals like that hallowed achievement by the Lisbon Lions under Stein. But while the league title remains the priority, for European qualification if nothing else, is it time to refocus their attentions away from bombastic domestic laurels? Does the power of three points trump the domestic treble?

Following an early ejection from the Viaplay Cup this season, Celtic have stolen a march in the Premiership and run their Group E opponents far closer than they did under Ange Postecoglou during his treble-winning campaign last year. With 11 players on the field and a healthier crop of first picks to choose from, Rodgers could well have engineered a first victory at that level for seven years in the Group E opener against a markedly average pot-one side in Feyenoord in Rotterdam. In the second fixture against Lazio in the east end of Glasgow, Celtic were the frayed leather of Daizen Maeda’s offside boot away from registering their first home win in the Champions League in a decade. And against LaLiga outfit Atletico Madrid on Wednesday night, Rodgers’ side went even closer to shedding a 10-year winless run at home in the competition, twice being pegged back to finish 2-2.

The Herald: Kyogo Furuhashi opens the scoring for Celtic against Atletico MadridKyogo Furuhashi opens the scoring for Celtic against Atletico Madrid (Image: Getty)

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That Champions League home form is the crux. The three games that matter most for Celtic in any group stage are their Parkhead fixtures. Ending that barren run against Feyenoord in the final Group E match next month after their return trip to Madrid should be non-negotiable for Rodgers and his players.

Next season, provided the Parkhead side go on to retain the title, will be their third crack at the Champions League proper in a row. And given the change of format due to take hold from 2024-25, they will have the chance to play eight sectional fixtures – four of those at home. The need to rebuild the aura around Celtic Park could hardly be more pronounced. Domestic form may ensure European involvement, but home form in Europe is crucial to any sense of progress under Rodgers this time around.

If good things come in threes, Celtic’s continued improvement and belief that they belong at this level will present the opportunity for unprecedented progress. Gordon Strachan and Neil Lennon reached the last-16 on three occasions between them in the years since O’Neill’s European heyday. Rodgers’ decision to return to Celtic will have been influenced in no small part by his desire to become the third modern manager to make such an impression at the club. Rodgers certainly thinks his team belong there; it is up to his players to prove it.