The LSE leads with extraverted logic (Te) and the LSI leads with introverted logic (Ti). Both are logical types and both are oriented toward precision, competence and the reliable management of practical systems. Te works outward: organising resources, driving toward results, holding processes to account against deliverables. Ti works inward: checking internal consistency, verifying structural integrity, building frameworks that are correct from the inside out. Each type's leading function is the other's seventh, Ignoring function: the LSE's Te sits seventh in the LSI's stack and the LSI's Ti seventh in the LSE's, so each is capable in what the other leads with but does not value it.
Common friction points
The LSE can find the LSI's inward orientation frustrating: precision as an end in itself rather than in service of actual delivery. The LSI can find the LSE's outward pace somewhat underprepared: effective at producing outputs, but not always careful enough about the architecture underlying them.
Neither type is indifferent to the other's domain; both recognise the logical seriousness they share. The Extinguishment dynamic produces a specific mutual dampening rather than hostility: each type tends to find the other's mode comprehensible but draining to engage with over time. Clear role separation, with each type operating in their natural domain, tends to produce better outcomes than sustained close collaboration.
Where each type's functions land
The second functions complete the picture. The LSE's Si is the LSI's Demonstrative Si and the LSI's Se is the LSE's Demonstrative Se: the LSI can keep things comfortable and orderly, and the LSE can be forceful, but each treats that as a side skill. With the leading functions already in each other's Ignoring position, the whole working style of each type is something the other can do and does not prize.
Their needs land on each other's Role. The LSE's Suggestive Fi is the LSI's Role Fi, and the LSI's Suggestive Fe is the LSE's Role Fe, so each receives a correct but effortful version of the personal warmth they most want. Their weak spots sit in each other's Mobilising: the LSE's Vulnerable Ni is the LSI's Mobilising Ni and the LSI's Vulnerable Ne is the LSE's Mobilising Ne. Neither is equipped to calm the other's worries about the future or about unpredictable change.
Two capable rule-keepers with the same blind spots tend to cope well with routine and less well with the unexpected. Agreeing in advance who decides in a crisis, and keeping each other's areas of authority separate, tends to keep the relationship respectful.
How this Extinguishment plays out
The Delta-Beta logic-leading Extinguishment pair runs hard. The LSE produces operational management (Te) backed by sensory grounding (Si); the LSI produces structural rigour (Ti) backed by willingness to enforce (Se). Both are logic-leading and disciplined, both prize reliability and the maintained standard, both can be relied on to hold the line when pressure rises. The opening contact has a quality of mutual respect between two rule-keepers: two figures for whom the system is not a suggestion.
The systematic inversion runs through every function letter. The LSE's outward-operational logic is inverted by the LSI's inward-structural logic; the LSE's inward-sensory grounding is inverted by the LSI's outward-defensive force. Discussion is fluent throughout; agreement on what should be done tends to be elusive. The Delta-Beta quadra divide intensifies the gap: Delta operations serve craft and sustainability, Beta structure serves mission and hierarchy, and the partners struggle to agree on which logic the discipline should ultimately answer to.
Where this pair functions: certain institutional partnerships in which the LSE handles operations and the LSI handles compliance, family configurations in which one parent runs the household and the other enforces the rules, occasional professional pairings in regulated industries where both modes are needed in clearly demarcated roles. The pair is reliably productive in disciplinary work and tends to become tiring in sustained close contact. Delta-Beta logic-leader Extinguishment runs strict and quietly destabilising.
The Extinguishment row on LSE in relationships and LSI in relationships places this pairing among the other relations each type has.